An article at discovermagazine.com has an astronomer (Chopo Ma) saying that if "one of them [quasars] were shooting laterally across the sky at the speed of light, it would, to us, appear motionless."
Wow, so the article is telling us about how astronomers use these quasars for measuring the Earth, but what else could they be used for?
Also, how long would it have to travel laterally at c before we would notice any differences in it's location (assuming it's, say... 14 billion light years away)?
The scale of our universe will never cease to blow my mind.
here's a link: Quasars Say Earth Is 1/2 a Pinkie Smaller